Device for the control of the mutual removal and approching movement of lateral conveying units in a carton sealing and/or closing machine

Abstract

A sliding plunger with rack-shaped opposite sides controls opposite rotations of a pair of rotating sector gears, with which integrally rotate two arms extending up to the proximity of the conveying units. Connecting rods are finally interposed between said arms and said conveying units to transform the rotary motion of the arms into a corresponding translatory motion of said conveying units in opposite senses along fixed rectilinear guides transversally disposed with respect to the carton support base. The control of the sliding of the rack plunger can be given by a pneumatic cylinder or by a hand-control lever. There can be provided adjustable means for limiting the sliding plunger stroke in the sense corresponding to the mutual removal of the conveying units and elastical thrust means acting on the same plunger in the opposite sense. The connecting rods moreover can be provided with a succession of holes, which can be alternatively chosen to change the distance among their points of pivotment with the rotating arms and the conveying units.

I claim: 
     
       1. Device for the control of the mutual removal and approaching movement of lateral conveying units in a carton sealing and/or closing machine of the kind including a carton support base and, along two opposite sides thereof, a pair of conveying units slidingly mounted on fixed transversal guides of the base so as to be approachable each other to realize a conveying engagement with the carton sides and then movable away from each other for the return to rest position, characterized in that it comprises a rectilinearly sliding plunger with rack-shaped opposite sides, control means of the sliding of said plunger, a pair of rotating sector gears in engagement with said rack sides of said plunger to transform the rectilinear sliding of the same plunger into opposite corresponding rotations of said sector gears, a pair of arms extending from said sector gears up to the proximity of said conveying units and integrally rotating with the same gears, and a pair of connecting rods connected to said arms and said conveying units to transform the rotating movement of said arm into a corresponding translatory motion of said conveying units in opposite senses along said guides. 
     
     
       2. Device according to claim 1, characterized in that said control means are constituted by a fluid-dynamic cylinder, on the piston stem of which said sliding plunger is fixed. 
     
     
       3. Device according to claim 2, characterized in that it comprises adjustable means interacting with said plunger for the delimitation of its stroke in the sense corresponding to the mutual removal of said conveying units. 
     
     
       4. Device according to claim 3, characterized in that said adjustable means are constituted by a hand-operation lever, a part of which is unidirectionally engageable by a pin integral with said plunger at the end of said stroke defined by the same plunger. 
     
     
       5. Device according to claim 4, characterized in that said lever is operated through the rotation of a threaded shaft engaged with a female thread fixed to said lever. 
     
     
       6. Device according to claim 1, characterized in that said plunger is mounted on a sliding stem and said control means are constituted by a hand-operation lever, a part of which is in bidirectional engagement with a nut in its turn slidingly mounted on said stem, elastical means which stress said plunger against said nut in the sense corresponding to the mutual approaching of said conveying units being provided. 
     
     
       7. Device according to claim 6, characterized in that said lever is operated through rotation of a threaded shaft engaged with a female thread fixed to said lever. 
     
     
       8. Device according to claim 1, characterized in that said connecting rods provide a succession of pivot holes for said arms and said conveying units, said holes being alternatively chosen to correspondingly change the distance among the points of pivotment with said arms and said conveying units.